Valve for dispensing two liquids at a predetermined ratio

ABSTRACT

A post-mix beverage valve provides for automatic, accurate beverage ratioing. A valve body can be assembled, and includes a water flow hard body, syrup body and common nozzle body. The water and syrup flow bodies define flow channels and include one end for connection to water and syrup respectively, and opposite ends for fluid connection to the nozzle body. The water flow channel includes a turbine flow sensor connected to a micro-controller determining the water flow rate. The syrup flow channel includes a flow sensor, two MEMS pressure sensors, monitoring the syrup. The sensors are connected to the micro-controller and positioned about an orifice and senses sense a differential pressure indicative of syrup flow rate solenoid regulates flow of syrup through the syrup body. A stepper motor on the water body controls a rod in the flow channel in conjunction with a V-groove.

IN THE UNITED STATES PATENT AND TRADEMARK OFFICE Non-Provisional PatentApplication

This application is a continuation of application Ser. No. 10/361,353,filed Feb. 9, 2003, now U.S. Pat. No. 6,845,886, which is acontinuation-in-part of application Ser. No. 10/154,381, filed May 22,2002, now U.S. Pat. No. 6,705,489 which is a continuation of applicationSer. No. 09/872,624, filed Jun. 1, 2001, now abandoned, which is acontinuation-in-part of application Ser. No. 09/870,297, filed May 30,2001, now U.S. Pat. No. 6,648,240.

FIELD OF THE INVENTION

The present invention relates generally to dispensing valves and inparticular to such valves having active ratio control apparatus

BACKGROUND OF THE INVENTION

Post-mix beverage dispensing valves are well known in the art and aretypically used to mix together two beverage constituents at a desiredratio to produce and dispense a finished drink. Such constituentsgenerally consist of a concentrated syrup flavoring and diluentcomprising carbonated or uncarbonated water. Various control strategieshave been employed to maintain the desired syrup to water ratio.“Piston” type flow regulators are a well known purely mechanical systemthat employs spring tensioning of pistons that constantly adjust thesize of orifice flow openings to maintain the desired ratio between thefluids. However, a failing with such systems is that they require bothfluids to be held within relatively narrow flow rate windows in order towork effectively. As is well understood, differences in ambienttemperature, syrup viscosity, water pressure and the like can allconspire to affect one or both of the flow rates to a degree that thedrink is ratioed improperly becoming either too dilute or tooconcentrated. As a result thereof, a drink that is too sweet can wastesyrup costing the retailer money, and whether too sweet or notsufficiently so, presents the drink in less than favorable conditions,also reflecting negatively on the retailer as well as the drink brandowner.

Volumetric piston dispense systems, as differentiated from the abovepiston based flow regulators, attempt to measure the volumes of eachliquid using the known volume of a piston and the stroke thereof. Thus,two pistons, one for the syrup and one for the water are drivensimultaneously by the same shaft or drive mechanism and are sized toreflect their desired volume ratio difference. Thus, operation of bothpistons serves to move the desired volume ratio of each of the fluidsfrom separate sources thereof to the dispense point or nozzle of thevalve. However, these systems have met with difficulty in that thereinherently exists a mechanical complexity relative to providing forinlet and outlet lines to each piston and providing for the correcttiming of the opening and closing of such lines. Such complexityincreases cost, imposes manufacturing difficulties and reduces operatingreliability. Also, there exist size constraints that require the pistonsto be relatively small resulting in high operating speeds that lead tocorresponding seal and other mechanical wear issues, as well asundesired pumping phenomena where less than a full volume is moved witheach pump stroke. Naturally, such wear and pumping inaccuracy problemscan negatively impact the ratio accuracy.

Electronic post-mix valves are also known that utilize sensors fordetermining the flow rate of either the water, the syrup or both, andthen, through the use of a micro-controller, adjust “on the fly” theflow rates of either or both of the water and syrup. In addition, hybridsystems are known that utilize both a volumetric piston approach for thesyrup and a flow sensing of the water flow. However, such post-mixvalves continue to be plagued with cost and reliability problems. Thesensors, for example, can be both costly and unreliable. Thus,maintenance of such post-mix valves by trained service techniciansremains a large part of the life cost thereof. In general, it appearsthat the ratioing technology employed in such electronic valves, whileuseful in large scale fluid ratioing applications, does not translatewell into the relatively small size requirements required of suchvalves.

Accordingly, there is a great need for a post-mix valve that canaccurately maintain the proper drink ratio consistently over timeregardless of changes in temperature, flow rate and so forth and that islow in cost both as to the purchase price and the maintenance thereof.

SUMMARY OF THE INVENTION

The present invention comprises a post-mix beverage dispensing valvethat provides for automatic and accurate fluid beverage constituentratioing, and that is reliable and relatively inexpensive to manufactureand operate. A valve body is designed to be easily assembled anddisassembled by hand without the need for hand tools, and includes awater flow body and a syrup flow body releasably securable to a commonnozzle body portion. The water and syrup flow bodies each include ahorizontally extending flow channel fluidly intersecting with avertically extending flow channel. The horizontally extending channelsof the water and syrup flow bodies each include open ends for connectionto sources of water and syrup respectively, and include fluid flowsensors. When secured together, the water, syrup and nozzle bodies aresecurable as an intact unit to an L-shaped support plate having ahorizontally extending base portion and a vertically extendingconnection facilitating end. A quick disconnect block provides forreleasable fluid tight sealing with the open ends of the horizontalwater and syrup channels and, in turn, releasable fluid tight sealingwith fittings extending from a beverage dispense machine. The bottom endof the support plate includes a hole centered below a bottom end of thenozzle body through which a nozzle is secured to the nozzle body. Waterand syrup channels in the nozzle body deliver the water and syrupthereto for mixture within the nozzle for dispensing therefrom into asuitable receptacle positioned therebelow. The syrup channel in thenozzle body includes an adjustment setting mechanism that serves as agross setting for the syrup flow rate within a certain desired range.

The water body horizontal channel flow sensor is of the turbine type anddisposed in the channel and includes hall-effect electronics fordetermining the rotational velocity of the turbine. That velocityinformation is provided to a micro-controller for determining the flowrate of the water. The syrup body horizontal channel sensor comprises apair of strain gauge type pressure sensors mounted to and in an exteriorwall portion of that channel and extending therethrough so that theoperative parts thereof are presented to the syrup stream. The sensorsare also connected to the micro-controller and are positioned on eitherside of a restricted orifice washer positioned in the flow stream. Thesyrup flow sensors serve to sense a differential pressure from which theflow rate of the syrup can be interpolated by the micro-controller.

The vertical flow channel of the water body has a stepper motor securedto a top end thereof and a “V”-groove type flow regulator and valve seatat an opposite bottom end thereof. An actuating rod extends centrally ofthe vertical flow channel and is operated by the stepper motor to movelinearly therein. The rod includes a tapered end for cooperativeinsertion through the center of a coordinately tapered central hole ofthe V-groove regulator. A tip end of the tapered rod end cooperatessealingly with a seat to regulate flow of the water past the seat andinto the nozzle body. The stepper motor is connected to a suitable powersource and its operation is controlled by the micro-controller.

A solenoid having a vertically extending and operating armature issecured to a top end of the vertical flow channel of the syrup body. Thearmature is operable to move in a downward direction through thevertical syrup flow channel and has a distal end that cooperates with aseat formed in the nozzle body positioned centrally of that verticalflow channel at a bottom end thereof. The solenoid is also connected toa suitable power supply and controlled by the microcontroller.

An outer housing is secured to the support plate and serves to cover andprotect the valve body sections, actuating devices and an electronicsboard containing the electronic micro-controller based control. Thevalve can be actuated by various means including, a lever actuatedmicro-switch or one or more push switches on the front face of thevalve.

In operation, actuation of a valve switch causes the syrup solenoid toopen and the stepper motor to retract the linear rod to a predeterminedposition away from its seat. The syrup and water then flow through thenozzle body to the nozzle and are subsequently mixed together fordispensing into a cup of other receptacle. As the water is flowing, itrotates the turbine flow sensor and the rotational speed thereof istranslated into a flow rate by the micro-controller. At the same time,the differential pressure sensors are sensing the pressures on each sideof the restricted orifice and the micro-controller is, based on thatinformation, calculating a flow rate for the syrup. It will beappreciated by those of skill that the position of the linear rodtapered end vis a¹ vis the V-groove regulator, changes the size of theopening leading to the nozzle body through which the water must flow.Thus, the flow rate of the water can be adjusted in that manner inproportion to the size of that opening whereby the stepper motor can beactuated to position the linear rod tapered end at any point betweenfull open and full closed. Therefore, in the valve of the presentinvention, the micro-controller first determines the flow rate of thesyrup and then adjusts the flow rate of the water accordingly in orderto maintain a pre-programmed ratio between the two liquids at apreprogrammed or desired flow rate. A gross adjustment of the syrup flowrate is provided by the adjustment means in the nozzle body and servesto determine a range as, for example, between a high flow and low flowapplication, such as, between a 1½ or 4 ounces per second dispense rate.

A major advantage of the preset invention is the combination of theadjustable linear actuation of the rod that interacts with v-grooveregulator to regulate the flow rate of the water. This approach is quiteaccurate, is reliable and low in cost. Determining the flow rate of thewater through the use of a turbine flow meter has also proven reliableand low in cost. A further major advantage of the present invention isthe use of a microelectronic strain gage type differential pressuresensor approach for determining the syrup flow rate. Syrup has proven tobe a difficult substance to work with owing in large part to itsviscosity, the temperature sensitivity of that viscosity and that it canbe corrosive and harbor the growth of microorganisms. Themicroelectronic sensors have been found herein to be suitable for usewith beverage syrups in that they are able to accurately sensevariations in the flow rate thereof without much effect as to viscositychanges, and are not degraded chemically over time. In addition, theparticular mounting of the sensors requires a very small area of contactwith the syrup resulting in a structure that does not cause any type ofsyrup build up or cleanliness concerns. The syrup flow sensing approachof the present invention provides the further advantage of alsoproviding for a valve that is relatively compact, light in weight andlow in cost.

The ability of the valve of the present invention to be disassembled byhand, including the internal components of the water, syrup and nozzlebodies provides for ease of manufacture and repair thereby also reducingthe resultant purchase and life costs thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the structure, function, operation and theobjects and advantages of the present invention can be had by referenceto the following detailed description which refers to the followingfigures, wherein:

FIG. 1 shows a perspective view of the valve of the present invention.

FIG. 2 shows a further perspective view of the invention herein with theouter cover removed.

FIG. 3 shows an exploded view of the valve herein and including a quickdisconnect block.

FIG. 4 shows a perspective view of the base plate.

FIG. 5 shows a side perspective view of the water body assembly.

FIG. 6 shows a cross-sectional view of the water body assembly.

FIG. 7 shows a perspective view of the v-groove regulator.

FIG. 8 shows a top plan view of the v-groove regulator.

FIG. 9 shows an enlarged plan cross-sectional-view along lines 9 a ofFIG. 8.

FIG. 10 shows an enlarged plan cross-sectional view along lines 9 b ofFIG. 8.

FIG. 11 shows a perspective view of the syrup body assembly.

FIG. 12 shows a side plan cross-sectional view of the syrup bodyassembly.

FIG. 13 shows an enlarged perspective view of the syrup body.

FIG. 14 shows a top plan view of the syrup body.

FIG. 15 shows and enlarged cross-sectional plan view of the differentialpressure sensor portion of the syrup body assembly.

FIG. 16 shows and enlarged cross-sectional plan view of the flow washer.

FIG. 17 shows an exploded perspective view of the nozzle body.

FIG. 18 shows a top plan view of the nozzle body.

FIG. 19 shows a bottom plan view of the nozzle body.

FIG. 20 shows a perspective cross-sectional view of the nozzle body.

FIG. 21 shows an exploded perspective cross-sectional view of the nozzlebody, syrup flow adjustment insert and retainer.

FIG. 22 shows a further cross-sectional view of the nozzle body asretained in the base plate.

FIG. 23 shows an exploded perspective view of the syrup and water bodyassemblies along with the nozzle body.

FIG. 24 shows a top plan view of the syrup and water body assembliesindicating their manner of attachment to the nozzle body.

FIG. 25 shows a perspective view of the syrup and water body assembliessecured to the nozzle body.

FIG. 26 shows a top plan view of the syrup and water body assembliessecured to the nozzle body.

FIG. 27 shows a diagram of the flow characteristics of the groovedregulator of FIG. 29 a.

FIG. 28 shows a schematic representation of a cross-section of theregulator of FIG. 29 a.

FIG. 29 a shows a top plan view of an embodiment of a grooved regulatorhaving four notches.

FIG. 29 b shows a top plan view of a grooved regulator having one notch.

FIG. 30 shows a diagram of the flow characteristics of the groovedregulator of FIG. 32.

FIG. 31 shows a schematic representation of a cross-section of theregulator of FIG. 32.

FIG. 32 shows a top plan view of a further embodiment of a groovedregulator having two notch pairs each pair having a different depth.

FIG. 33 shows a diagram of the flow characteristics of the groovedregulator of FIG. 35.

FIG. 34 shows a schematic representation of a cross-section of theregulator of FIG. 35.

FIG. 35 shows a top plan view of a further embodiment of a groovedregulator.

FIG. 36 is a simplified schematic of the electronic control of thepresent invention.

FIG. 37 shows a graphical representation of the operation of the steppermotor and syrup solenoid.

FIG. 38 is a graphical representation of the allowable ratio errorlimits.

FIG. 39 shows a flow diagram of the control logic of the presentinvention.

FIG. 40 shows a perspective view of a ratio testing device.

FIG. 41 shows a perspective view of a further embodiment of the presentinvention.

FIG. 42 shows a perspective view of the syrup flow body of theembodiment of FIG. 41.

FIG. 43 shows a cross-sectional view of the syrup flow body of FIG. 42.

FIG. 44 shows a graphical representation of the operation of the syrupand water flow bodies of the embodiment of FIG. 41.

FIG. 45 shows a flow diagram of the operation of the valve embodiment ofFIG. 41.

DETAILED DESCRIPTION

The valve of the present invention is seen in FIG. 1 and generallyreferred to by the numeral 10, and includes a removable outer protectiveshell 12. Removal of shell 12, as seen in FIGS. 2 and 3, reveals variousinternal valve components including a base plate 14, a quick disconnectmounting block 16, a syrup flow body assembly 18, a water flow bodyassembly 20, a nozzle body assembly 22 and a printed circuit boardelectronic control 23. Base plate 14 includes a front push buttoncontrol portion 24 having a plurality of diaphragm type switches 24 a–24e for operating valve 10. Switch 24 e causes valve 10 to dispense for aslong as it is operated/pushed. In the same manner, a lever arm 19 canalternatively be used to operate a switch, not shown, to cause valve 10to dispense. As is well understood, arm 19 is pivotally suspended frombase plate 14 and is typically actuated by pushing a cup to be filledthereagainst followed by retraction of the cup once it is filled.Switches 24 a–e are of the portion control variety wherein selection ofa particular switch serves to operate valve 10 to dispense apreprogrammed volume of drink. It is also known to have the valve turnedoff automatically based upon a sensing that the cup is full.

Base plate 14 also includes a vertical rear portion 25 having formed ina shelf area 25′ thereof two semicircular annular grooves 25 a and 25 b.Plate 14 further includes circuit board retaining slots 26 a and acircuit board retaining clip 26 b as well as a pair of nozzle bodyretaining clips 27. A nozzle housing 28 is secured to nozzle body 22through a hole in a bottom surface of plate 14, the hole defined by aperimeter shoulder S. Quick disconnect 16, as is well understood in theart, includes two barrel valves therein, not shown, for regulating theflow of water and syrup. The barrel valves are opened when the top andbottom trapezoidal insets 16 a are received in correspondingly sizedslots 16 b in base 14 and locked thereto. Disconnect 16 includes fluidoutlets 30 a and 30 b for fluid tight connection with syrup bodyassembly 18 and with water body assembly 20, respectively. Furtherdescription of disconnect 16 and the details of its operation are seenby referring to U.S. Pat. No. 5,285,815, which disclosure isincorporated herein. As is known disconnect 16 is secured to a beveragedispensing machine, not shown, and provides for quick fluid connectionof valve 10 thereto.

As seen by now referring to FIGS. 5–10, water body assembly 20 includesa plastic body portion 35 having a vertical flow regulating housingportion 35 a and a horizontal flow meter housing portion 35 b. A steppermotor 36 is secured to a top end of housing portion 35 a and operates avertically positionable shaft 37. In one embodiment of the presentinvention where the total flow rate is between 1 and ½ to 6 ounces persecond, motor 36 operates on 3–5 volts DC and provides for a reversibleshaft travel of 0.001 inch per step at a rate of 1 to 1000 steps persecond. Shaft 37 extends through upper fluid sealing rings 38 and has adistal conical end 42 and a seating shoulder 43. As seen in the enlargedviews of FIGS. 7–10, a specialized grooved fitting 44 is retained withina bottom end of housing 35 a and sealed therein by an O-ring 46 receivedwithin a perimeter annular groove 48. Fitting 44 is circular having aheight or thickness represented by the letter “H”. Fitting 44 is formedby the drilling of a central hole or bore 50 therethrough having adiameter “D” followed by the formation of a plurality of V-shapedgrooves or notches formed therein and extending downward from a topfitting surface 51. In the disclosed embodiment, there are four groovesconsisting of two deep grooves 52 and two shallow grooves 54. Theangular or cut away portion of grooves 52 represented by angularsurfaces 56 extend to a bottom surface 58 of fitting 44. Thecorresponding surfaces 60 of grooves 54 terminate at a pointapproximately midway of the height or thickness H of fitting 44. Thevertical or internal angular steepness of grooves 52 and 54 can berepresented by angles A1 and B1 respectively. The width of the grooves52 and 54 can be represented by top surface angles A2 and B2respectively. A radiused or chamfered edge 62 extends around a topperimeter of grooves 52 and 54 and bore 50. As seen in FIG. 7, shaft 37is vertically positionable through fitting 44 and at its bottom mostposition shoulder 43 seats against a perimeter edge 64 of a circularseat 66. It will be understood herein below that seat 66 is retained innozzle body 22.

Water body portion 35 b includes an inlet fitting 70 for receivingoutlet 30 b of quick disconnect 16. Inlet 70 has an outer annular ridge72 that serves to cooperate with annular groove 25 b of rear plateportion 26. A turbine type flow meter 74 is held within flow meterportion 35 b. Portion 35 b, with meter 74 therein, is then sealinglysecured to body portion 35 a, by for example sonic welding, for fluidtight securing in flow cavity 75. In addition, an O-ring 76 provides forfurther fluid isolation of the exterior of meter 74 from the water flowstream passing from inlet 70 into and through body portion 35 a. Flowmeter 74 is of a turbine type, well known in the art, and in thebeverage valve embodiment of the present invention, is selected to workin an aqueous environment in a flow stream varying between approximately0.25 to 11 ounces per second, having a sensitivity of 6000 pulses persecond and exposed to pressures from 0.0 to 580 psi. Also in thepreferred embodiment, turbine flow meter 74 has an exciter voltage inthe range of 5–24 volts and uses approximately 12 milliamps of currentand includes a circuit board 78 formed as a disk having a central holeon which are mounted optical sensors for determining the rotation of therotatively mounted turbine (not shown). Wires (not shown) extend fromdisk 72 and extend through holes 79 for connection to main circuit board23. As is understood, main control circuit board 23 embodies a microcontroller that determines the rotation rate of the turbine of flowmeter 74 and from that number calculates a flow rate of the waterpassing through flow portion 34. It will be appreciated that thesecuring of meter 74 in body portion 35 b and the sealing thereof tobody portion 35 a along with the use of O-ring 76 also serves to isolatecircuit board disk 78 from any damaging fluid contact. Body portion 35 aincludes a pair of locking tabs 35 c extending from a bottom endthereof.

As seen in FIGS. 11–16, syrup flow body 18 includes a plastic flow bodyportion 80 having locking tabs 81, an inlet end 82 having a perimeterannular ridge 84 for cooperating with corresponding groove 25 a of baseplate vertical portion 25. Inlet 82 receives outlet 30 a of quickdisconnect 16 for providing syrup into a central horizontal flow channelcomprised of a first channel portion 86 a and a second channel portion86 b. Channel portion 86 b communicates with a fluid cavity 88 wherein avertically extending flow channel segment 90 extends. Flow segment 90defines a portion of a vertical flow channel 92 and has a proximalperimeter seat end 94. A normally closed solenoid 96 operating at 24volts dc is secured to a surface area 97 of body portion 80 and includesand armature 98 having a resilient seat end 98 a for closing againstseat 94. Flow body 80 includes two circular recesses 100 a and 100 bthat communicate fluidly to flow channel portions 86 a and 86 b throughsmall orifices 102 a and 102 b respectively. Two pressure sensors, notshown, one associated with each recess 100 a and 100 b, are exposed tothe flow of syrup through channel portions 86 a and 86 b. The pressuresensors are of the well known pressure sensing diaphragm ormicro-electromechanical (MEMS) type and in the disclosed beverage valveembodiment herein are selected to respond to pressures in the range of0–100 psi. Such sensors in the preferred embodiment operate at 3 to 5volts dc, and need to have an accuracy or pressure non-linearity of lessthan 1%. In the preferred form, the sensors are individually andseparately mounted to a common circuit board 104 which includes theelectronics and connectors 106 for communicating sensed pressure data tocontrol board 23. Ribbon type connectors, not shown, provide for theelectrical connection from connectors 106 to board 23. O-rings 108provide for fluid tight sealing of the pressure sensors from theremainder of the board 104. Board 104 is held in place in against a flatsurface area 110 by suitable attachment means, such as, food gradeadhesive, as well as by a retainer 112 which is snap fittingly securedto flow body 80. As understood by referring to FIGS. 15 and 16, a flowwasher 114 is retained at the intersection of flow channels 86 a and 86b and has a thickness T, a central bore 116 half the length of which isenlarged by a chamfered edge 118 extending at an angle C. In thepreferred form, the chamfered edge side of washer 114 faces in anupstream direction as will be understood by the direction of syrup flowindicated by the arrows of FIG. 15. As is known, the chamfered edge 118serves to reduce the apparent thickness T. Those of skill willunderstand that the chamfer typically can face in a downstream directionproviding the upstream edge is sharp, i.e., of a radius substantiallyless than the diameter of the orifice.

As seen in FIGS. 17–23, nozzle flow body assembly 22 includes retainerstops 120 a and 120 b each defining tab receiving grooves 122 a and 122b respectively. Annular recesses 124 a and 124 b serve to retainresilient fluid sealing washer and water seat 66 and a further resilientfluid sealing washer 126 respectively and are surrounded by flatcircular areas 127 a and 127 b. A vertical syrup passage 128 fluidlyconnects with a horizontal syrup passage 130, which, in turn, fluidlycommunicates with a central syrup discharge outlet 132. Similarly, avertical water passage 134 fluidly connects with a horizontal waterpassage 136, which, in turn, fluidly communicates with a water dischargeoutlet 138. A syrup flow adjustment piece 140 includes a protruding edgeportion 142, a central bore 144 and a V-shaped slotted opening 146extending therethrough into the bore 144. Adjustment piece 140 is heldwithin syrup discharge outlet 132 wherein edge portion 142 is insertedwithin rotation limiting slot 148 and is held within outlet 132 by adisk shaped retainer 150. Retainer 150 includes a neck portion 152 forclose fitting insertion into outlet 132 and includes a water-flow hole154 having an annular ridge 156 for insertion into water dischargeoutlet 138. Retainer 150 is permanently secured to nozzle body 22 by,for example, sonic welding thereto around its perimeter edge 158 and bysonic welding between outlet 138 and ridge 156. As seen in FIG. 16,adjustment piece 140 includes slots 160 in the bottom end surfacethereof. Nozzle body 22 also includes a pair of snap fitting tabs 162for insertion into and snap-fitting securing thereof with retainers 27of base plate 14. A fluid mixing insert 170 includes a neck portion 172for insertion into retainer 150 and is fluidly sealed therewith by anO-ring 174. Mixing insert includes a conical surface area 176 and twohorizontal circular plates 178 and 180 positioned therebelow. Plates 178and 180 include a plurality of passages 182 therethough and theperimeter edges thereof are closely adjacent an interior flow surface184 of nozzle housing 28. As will be understood by those of skill,nozzle housing 28 is fluid tightly secured to nozzle body 22 by atwisting engagement of tabs 186 thereof with retainers 164 thereofagainst an O-ring 188 therebetween. Mixing insert 170 also includes acentral syrup channel 190 for directing syrup from outlet 132 to angledexit orifices 192.

By referring to FIGS. 23–26, the manner of assembly of syrup flow bodyassembly 18, water flow body assembly 20 and nozzle body assembly 22 canbe understood. In particular, the lower end of syrup body portion 35 iscentered on and pressed against surface area 127 a after which it isturned counterclockwise as indicated by the arrows CC in FIG. 22 whereintabs 81 fit within grooves 122 a of stops 120 a. This rotationalmovement of syrup body 18 is limited by stops 120 a to place syrupassembly 18 in the proper orientation. In a similar manner, the lowerend of water body portion 35 a is centered on and pressed againstsurface area 127 b after which it is turned clockwise as indicated byarrows CW wherein tabs 35 c fit within grooves 122 b. This rotationalmovement of water flow body 20 is limited by stops 120 b to place it inthe proper orientation. The assembly of the three flow bodies is thenlowered into plate 14 wherein snap tabs 162 are received withinretainers 27 providing for snap-fitting securing therebetween. It willbe understood that a lower portion of annular ridges 84 and 72 of flowbodies 18 and 20 will rest on and be received in annular grooves 25 aand 25 b respectively. Nozzle housing 28 is then secured to nozzle body22 in the manner above described capturing mixing insert 170therebetween. Control electronics board 23 can be fit into slots 26 awherein retainer 27 snap fits into a slot, not shown, in board 23thereby retaining board 23 in the vertical orientation, as seen in FIG.2. Those of skill will understand that the various electricalconnections between flow sensor 74, pressure sensing board 106, steppermotor 36, solenoid 96 and circuit board 23 can be facilitated byreleasable plug-in connectors. Housing 12 can then be secured to plate14 by any of a variety of snap fitting releasable type securing means.

As is well understood, the general operation of valve 10 secured to apower supply to run stepper motor 36, solenoid 96 and-control board 23and to a quick disconnect 16, which disconnect 16 is suitably secured toa beverage dispenser and fluidly connected to a source of syrup anddiluent. When valve 10 is secured to disconnect 16 pressurized sourcesof syrup and diluent are supplied to valve 10. When a suitable dispensebutton is selected by use of one of switches 24 a–d, a particular volumeof drink is requested as is previously programmed in the control ofcircuit board 23. Control board 23 signals stepper motor 36 to withdrawshaft 37 from contact with seat 66 thereby permitting the flow of waterthrough body portion 34 and into nozzle body assembly 22. After a shortdelay, to be explained and described in greater detail below with regardto the specific operation of valve 10, solenoid 36 is opened permittinga flow of syrup through syrup body 80 to nozzle body assembly 22. Thesyrup and water then flow to mixing insert 170 and exit nozzle housing28 into a cup held therebelow. As is well understood the water and syrupflows must flow at a pre-established ratio, for example, five partswater to one part syrup. Valve 10 accomplishes the maintenance of thisratio by simultaneously determining the flow rate of the syrup and thewater and adjusting the flow rate of the water to the syrup. It will beappreciated by those of skill that the flow rate of the syrup isdetermined by a differential pressure flow rate sensor as is comprisedof flow sensor chip 104, the flow washer 115 and flow channel portions86 a and 8 b. It will be understood that as syrup flows through thecentral orifice of washer 115, different fluid pressures are presentedto the up and down stream pressure sensors positioned on board 104 andabove orifices 102 a and 102 b respectively. A micro-controller ofcontrol board 23 is programmed therewith and with variouslyexperimentally determined data contained in look-up tables in order topermit the calculation of the actual syrup flow rate. At the same timeas the syrup flow rate is being determined the water flow rate is beingmeasured as a function of the rotational speed of the turbine flowsensor 74. This water flow rate is determined by the control of board 23and compared with the calculated syrup flow rate in real time. If theratio therebetween is not as is desired where, for example there is anexcess of water, the micro-controller signals stepper motor 36 to moveshaft 37 in a downward direction positioning conical surface 42 thereofcloser to seat surface 64 of seat 66, thereby reducing the openingtherebetween and lowering the water flow rate. Of course, those of skillwill realize that micro-controller must be able to provide rotationalinstructions to stepper motor 36 to effect the desired water flow rateadjustment. As is known, stepper motors, such as motor 36, can besignaled to rotate through a set number of 360 degree rotations and/orfractions thereof that correspond to a know linear distance movement ofthe shaft thereof.

If a standard circular valve seat is used having no regulator 44thereabove, the flow rate therethrough is not linear. In fact, a majorproblem has been that the flow rate as a function of the separationbetween the seat of a standard orifice and the effective end of theshaft can be complicated to determine and to control. However, the flowregulator 44 shown herein has been found to establish a substantiallylinear relationship between the shaft 37 position vis a¹ vis the seatand the fluid flow rate. As seen in FIG. 28, a generalized regulator 180is shown in cross section wherein flow rate therethrough is depicted inthe graph of FIG. 27. As a shaft 182 moves in the direction of arrow Aof FIG. 28, the flow rate of fluid through regulator 180 is shown in thegraph of FIG. 27 to increase linearly. The slope of that line can beunderstood to be a function of the size or number of grooves 184 inregulator 180 or 180′, as illustrated in FIGS. 29 a and 29 b. The slopecan be understood to be lower for regulator 180′ as seen in the dashedline of FIG. 27. FIGS. 30–35 show the effect of variously configuredgrooves. Regulator 186 of FIG. 32 includes, as does regulator 44, twosets of grooves, shallow grooves 188 and deep grooves 190. When shaft182 reaches the point within regulator indicated by vertical line L ofFIG. 31, the grooves 188 begin to contribute to the fluid flow and henceincrease the slope of the fluid flow as indicated at the slope changepoint 192 of FIG. 30. It can now be appreciated that the increase inflow area provided by the additional set of grooves allows shaft 37 totravel through a shorter linear distance but still provide the desiredincrease in flow rate. The angles A1 and A2 and B1 and B2, seen in FIGS.7–10, provide for increased flow rate in proportion to increase an insize thereof. Thus, the larger the grooves and the larger the bore 50,the more flow is permitted as the shaft withdraws. Of course, those ofskill will understand that all such dimensions and angles are highlyvariable depending on the flow rate range, the desired flow accuracy,the travel of the linear actuator and the like. In a beverage dispenseenvironment of 1 and ½ to 6 ounces per second, bore 50 can beapproximately 0.185 inch.

As seen in regulator 194 of FIG. 34, a single groove 196 includes afirst sloped portion 196 a a horizontal or linear portion 196 b and afurther sloped portion 196 c. As seen in the graph of FIG. 33, thesethree groove sections correspond with the flow rate curve portions 198a, 198 b and 198 c respectively. Thus, as shaft 182 withdraws fromregulator 194 the flow rate first increases due to the widening effectof groove portion 196 a. The flow rate then levels off as groove portion196 b represents a constant non-increasing flow area. The flow rate thenstarts to increase as the shaft is withdrawn past groove portion 196 cwherein the flow area is again increasing. FIG. 35 shows a regulator 200having a V-shaped groove 202 and also shows in dashed outline variousother regular geometric groove shapes such as a U-shaped groove 204 a, asquare shaped groove 204 b or a trapezoidal shaped groove 204 c. It willbe understood that these other groove shapes can be angled to providefor increasing grooved area and greater fluid flow as the shaft 182retracts. Thus, FIG. 35 illustrates that any of a wide variety of groovecross-sectional shapes and configurations can be used depending upon toachieve a linear flow as a function of shaft position within a groovedregulator. Thus, this linearity permits a relatively straightforwardcalculation by the control of board 23 as to the distance to move shaft37 in or out to follow the sensed syrup flow rate. Therefore, the waterflow rate is continually being adjusted in real time as a function ofthe sensed water flow rate and syrup flow rate.

A more detailed understanding of the manner of the operation of thecontrol of the operation of the present invention can be had byreferring to FIGS. 36–39. As seen in FIG. 36, a simplified schematic ofthe present invention shows control board 23 including a power supply210 and a micro-controller 212. Switches 24 a–e, turbine 74 anddifferential flow sensor board 104 provide input to micro-controller212. A connection port 214 is also connected to micro-controller 212 forpurposes of facilitating adjustment of the operation of valve 10 as willbe described in greater detail hereinbelow. Microprocessor 212 is alsoconnected to stepper motor 36 and solenoid 96 for controlling theoperation thereof. Power supply 210 includes a capacitor array 215 foremergency powering of the stepper motor 36. If power should fail, syrupflow will automatically stop as solenoid 96 is normally closed, i.e.power is required to hold it open. However, those of skill willunderstand that stepper motor 36 will remain at whatever position it isat when power is interrupted. Therefore, capacitor array 215 providespower to close stepper motor 36 if power is sensed to have failed.

As seen in FIG. 37, a graph of the operation of the stepper motor 36 isrepresented by solid line 216 and syrup solenoid 96 is represented by adashed line 218. Stepper motor opens at a time T₁ and the water flowsubsequently ramps up to a desired flow rate at time T₃. At time T₃,stepper motor movement stops. Syrup solenoid 96 opens at a time T₂ afterthe initiation of water flow, but prior to time T₃, and quickly reachesa peak flow. This delay in the initiating of the syrup flow is necessaryas those of skill will appreciate that stepper motor 36 can not open asquickly to it full flow position as can solenoid 96. Thus, if they wereopened simultaneously, the finished drink would be too rich in syrup,the desired in cup ratio not being achieved. Therefore, initiation of adispense into a cup by, for example, the pressing of switch 24 e,signals micro-controller 212 to first operate motor 36 and then to opensolenoid 96. At the close of dispense when the cup is full, switch 24 ecan be released causing the reverse to occur. Specifically, at time T₄motor 36 begins to close and then is fully closed at time T₆, andsolenoid 96 is signaled to close at time T₅ therebetween. Thisstaggering at closing, for the same reason stated above for opening,also serves to maintain the proper in cup ratio of syrup to diluent. Theparticular staggering time of the stepper motor and solenoid aredependent upon the type of stepper motor and solenoid used, the desiredratio between syrup and diluent water and the desired total dispense orflow rate of the two liquid combined

A further detailed explanation of the control of the valve of thepresent invention can be had by referring to FIGS. 38 and 39. Asillustrated graphically in FIG. 38, there exists a known orpredetermined in cup target ratio N. If the ratio of the drink is 5parts syrup to 1 part carbonated water, then the total volume of syrupand carbonated water in the cup must be ideally in that proportion, orwithin an acceptable error thereof. This is achieved by havingmicro-controller 212 keep track of two ratios, an instantaneous ratioand a total dispensed or in cup ratio. Thus, processor 212 isdetermining an instantaneous flow rate as a function of the differentialpressure sensor determination of the syrup flow rate and the waterturbine sensed flow rate of the water at a particular moment in time.Those of skill will understand that controller 212 makes suchcalculations many time per second and in a particular embodiment of theinvention, approximately 100 times per second. The in cup ratio issimply a calculation comprising a summation of the total syrup and waterflow as a function of the known flow rates thereof as have occurredduring a particular pour. Thus, at any point in time, processor 212knows the total volume that has been dispensed, the ratio of that totaldispense and what the ratio being dispensed at any particular point intime is. Processor 212 is programmed with an allowable positive in cupratio error E+ and an allowable negative in cup ratio error E− creatingan in cup error band indicated by the arrow B1 in FIG. 38. Processor 212is also programmed with an allowable positive instantaneous ratio errorI+ and an allowable negative instantaneous error I− creating aninstantaneous error band indicated by the arrow B2 in FIG. 38. With theforegoing in mind, a further understanding of the operation of thecontrol of the present invention can be had by referring to the flowdiagram of FIG. 39. A pour of beverage from valve 10 into a suitablecontainer position below nozzle 28 is initiated by an operator selectingone of the pour initiation switches 24 a–e. Pour initiation is seen inblock 220. At block 222, processor 212 determines if the in cup ratio isgreater than or equal to E+, less than E−, or within that error band,i.e. less than E+ and greater than E−. If the in cup ratio is greaterthan or equal to E+, at block 224 the instantaneous ratio is determined.If the instantaneous ratio is greater than I−, at block 226 steppermotor 36 is activated to move shaft in the closing direction reducingwater flow conversely, at block 228 if the instantaneous ratio is lessthan or equal to I− then no change is made to the position of stepper36. If at block 222 it is determined that the in cup ratio is less thanE− then at block 230 the instantaneous ratio is also calculated. If thatratio is less than or equal to I+, then at block 232 no change is madeto the position of stepper 36. However, if the instantaneous ratio aschecked at block 230 is less than I+ then the drink is too syrupconcentrated at that point and stepper 36, at block 234 is made to moveto increase water flow. Those of skill will understand that theinstantaneous ratio is being constantly calculated and occurs as thestepper motor 36 is moving either towards its seated closed position tomake the ratio less dilute or towards its full open position to make theratio more dilute. Thus, the control cycle back through block 222 untilthe sensed instantaneous ratio is within the in cup ratio error band. Atthat point at block 236 the instantaneous ratio is again determined andif it is less than E− the in cup ratio is calculated at block 238. Ifthe in cup ratio is less than N, stepper motor 36 is operated at block240 to increase the water flow. Conversely, if the in cup ratio at block238 is greater than or equal to N, then at block 242 no change is madeto the stepper motor position. If, at block 236 the instantaneous ratiois determined to be greater than E+ the in cup ratio is calculated atblock 244. If, at block 246 the in cup ratio is less than or equal to Nstepper motor 36 position is not changed. Conversely, if the in cupratio at block 244 is greater than N, then at block 242 stepper motor 36is operated to reduce water flow. If at block 236 the instantaneousratio is equal to N, then at block 250 no change is made to the positionof stepper motor 36. Those of skill will understand that the control asshown in FIG. 39 permits the instantaneous ratio to first be broughtwithin a wider instantaneous ratio band and then to be brought within anarrower in cup ratio error band. This approach was found to provide fora relatively smooth operation whereby the desired ratio N was approachedwithout the need for a lot of movement by stepper motor 36. The positionthat motor 36 is first opened to is determined by memorizing itsposition during the previous pour at the point at which the in cup ratioand the instantaneous ratio are equal or the closest. If there exists noprevious pour data, a default position is preprogrammed. When thedispense from valve 10 is manual, as by the use of switches 24 e orlever arm 19, dispensing is stopped when such switches are released.

It can now be appreciated that selection of a drink volume usingswitches 24 a–d signals microcontroller 121 to determine when the totalvolume dispensed is equal to the predetermined and selected small,medium, large or extra large volume. Thus, a further block 252 questionsif that preselected total volume has been reached. If it has, thendispensing is stopped at block 254. Due to variations in the manufactureof certain elements, such as, the turbine flow meter, the differentialpressure sensors and the like, it was found that there can exist adifference between the ratio that the valve is set at and the actual incup ratio that is dispensed. Thus, valve 10 can be adjusted or zeroed inthrough an actual pour test. As seen in FIG. 40, a brix cup 260 is showncomprising a clear plastic dual chambered cup having a syrup volume side262, a water volume side 264 and a divider 266 therebetween. As is knowna specialized separating nozzle is 268 is used in place of the regularnozzle 28 and insert [[170]]. Nozzle 268 includes a tube 270 forinsertion into the syrup discharge hole and directs the stream of syrupto syrup container portion 262. As is also understood, water flowsaround tube 270 and down into water container portion 264. In operation,valve 10 is actuated and allowed to dispense until the water reaches aparticular level as is indicated by the graduation marks 272. Since thesyrup stream is separated from the water, its volume can also bedetermined by ascertaining its level. By simply dividing the watervolume by that of the syrup the ratio therebetween can be calculated. Iffor example, a 5 to 1 ratio was desired however a 4.8 to 1 ratio wasdispensed, then the software of microcontroller 212 must be adjusted tocompensate therefor. This is done by connection of a device to port 214.Such a device can be a hand held computer or the like having the abilityto increment the ratio set point of the software control up or down asis needed upon an initial set up. It is also then possible thereby tosubsequently set valve 10 to a different ratio wherein the software willautomatically do so and take into account any such initial set upadjustments.

Valve 10 can be designed to dispense at various dispense rates, such as,1½ ounces per second, 4 ounces per second and 6 ounces per second.However, it was found that, since the syrup flow rate can not beadjusted during a dispense, it is important that it be capable of beingadjusted within various flow ranges suitable for the particular totaldrink flow desired. The control would otherwise have difficulties inmaintaining the correct ratio if the water and syrup flow rates were notat least generally matched. This gross adjustment of the syrup flow isaccomplished by adjustment of insert 140. As can be understoodtriangular shaped slot 146 is presented towards syrup orifice end ofsyrup flow channel 130. As insert 140 is rotated about its central boreaxis, more or less of the slot 146 is presented thereto thus permittinga greater or lesser flow respectively of syrup therethrough. Thus,rotation of insert 140 by a tool inserting into slots 160, after removalof nozzle housing 28 and the mixing insert, permits such grossadjustment of syrup flow. The aforementioned brixing cup 260 andadjustment nozzle 268 can be used to set the desired syrup flow rate.

A further advantage of the present invention can be seen to include themanner of assembly and disassembly thereof. When water body assembly 18and syrup body assembly 20 are connected to nozzle body assembly 22 andsecured to base 14, it will be appreciated that ridge 72 of water bodyassembly 18 and ridge 84 of syrup body assembly are received in annulargrooves 25 b and 25 a respectively. Furthermore, when quick disconnectis connected to base plate 14 the fluid coupling inserts 30 a and 30 bthereof are received in water body inlet end opening 70 and syrup bodyinlet end opening 84 respectively. This connection strategy serves tohold water body 18 and syrup body 20 in place as neither can be rotated.Thus, neither can be removed when fluidly connected to pressurizedsources of water and syrup. To be removed quick disconnect must first beremoved, but it can not be removed unless the barrel valves thereof havebeen closed. Thus, valve 10 can not be disassembled unless there existsno fluid pressure thereto. Clips 27 also serve to hold serve to hold theentire water, syrup and nozzle assembly in place joining thereof to base14. It can also be understood that the entire valve can be easilyassembled and disassembled by hand. Moreover, stepper motor 36 is apermanent portion of the water body assembly as is turbine flow meter74. Thus, any failure of that component simply involves change out witha new replacement. Such is also the case for the syrup body 20, thenozzle body 22 and the circuit board 23. Thus, the present invention isfully modular and easily and inexpensively repaired and serviced.

Valve 10 has been shown and described herein in its preferred beveragedispensing valve embodiment. However, those of skill will that variousmodifications can be made to the present invention without exceeding thescope and spirit thereof. For example, a variety of flow sensors areknown that could be substituted for turbine flow sensor 74 and/ordifferential pressures flow sensor 104, such as, coreolis and ultrasonicflow sensors. A “mechanical” sensor of the turbine type wherein the flowof water imparts a rotation thereto has been found to be sufficientlyaccurate, reliable and low in cost when applied to sensing water flow inthe present invention. The differential pressure sensing of the syruphas proven to be more accurate with the higher viscosity liquids such asa beverage syrup. Moreover, such sensing approach has proven reliable,acceptably accurate and low in cost. Those of skill will understand thatvarious embodiments of the invention herein could use a turbine flowmeter on both the diluent and concentrate side, or a differentialpressure flow sensor on each side, or indeed, could reverse the sensorsand use a turbine on the concentrate side and a differential flow sensoron the diluent side. Such selections would depend greatly upon thephysical nature of the fluids being combined, their individualanticipated flow rates, their ratio of combination, accuracy requiredand the like. It will also be apparent to those of skill that a linearactuating means, such as, a linear solenoid or pneumatic actuator couldbe substituted for stepper motor 36. The functional requirement beingthat shaft 37 is capable of being moved incrementally and held atvarious points between and including a fully open and a fully closedposition.

A further embodiment of the present invention is seen in FIGS. 41–43.Valve 300 is the same as valve 10 in most respects and common elementsthereof are indicated by the same reference numerals as previouslydescribed herein. The difference between valves 10 and 300 lies in thefact that there exists in valve 300 a different syrup module 302. Syrupmodule 302 instead of being operated by an on/off solenoid, as withwater module 18, is also operated by a stepper motor 304. Thus, module302 includes a shaft 306 having a conical or tapered distal end portion308 operating within a grooved flow control element 310. Control elementis essentially the same as element 44, however, those of skill willunderstand that the various dimensions thereof as to the particulargroove geometry and dimensions as well as that of the central bore canbe different from that of element 44 depending upon the ratio of theparticular syrup or concentrate to the diluent. Concentrate module 302therefore serves to control the flow rate of the concentrate in the samemanner as described previously herein for the control of the diluentflow rate by module 20.

Those of skill can appreciate that the use of two stepper motors inratioing valve 300 of the present invention provides certain advantagesover valve 10. Primarily, there exists the potential for more flexibleand accurate control of the ratioing process. For example, if the ratiois adjudged to be too lean, valve 300 can be controlled to eitherdecrease the diluent flow or increase the concentrate flow. Conversely,if the ratio is sensed to be too rich, the concentrate flow can bereduced or the diluent flow increased. Also, the staggering of theinitiation of the diluent and concentrate flows is not required as bothflows can be commenced simultaneously given that neither opening issubstantially mechanically different in terms of being slower of fasterthan the other. Thus, the initial volume of mixed liquids can be moreaccurately blended in a quantitative sense than is the case where anapproximation has to be made where there are mechanical differencesbetween two valve opening strategies.

A better understanding of the flow control of valve 300 can beunderstood by reference to the pour profile graph of FIG. 44 and theflow control logic as seen in the flow diagram of FIG. 45. At block 320of FIG. 45, the control is awaiting a signal indicating the initiatingof a dispense. If an initiation is sensed, then at block 322 bothstepper motors 36 and 304 are operated to retract to predeterminedpositions to allow for a target total volume flow rate as is alsopredetermined and programmed into the control. Those of skill willunderstand that upon initial start-up a first or default position isused to position the shaft of each stepper motor. If there has been aprevious pour, then the initial positions for each stepper are the lastin-ratio positions. At the instant both stepper motors are opened andduring the entire dispense control 23 is determining the flow rate ofeach of the concentrate and diluent individually and calculatinginstantaneous and total or combined flow rates. As with each dispensethere exists a predetermined desired total combined flow rate of bothliquids and a predetermined desired ratio therebetween, those of skillwill appreciate that at any given instant there can exist sevendifferent possible conditions, namely:

1. A combined flow rate that is below the desired flow rate and wherethe ratio is too rich in concentrate.

2. A combined flow rate that is below the desired flow rate and wherethe ratio is too lean in concentrate.

A combined flow rate that is above the desired flow rate and where theratio is too rich in concentrate.

4. A combined flow rate that is above the desired flow rate and wherethe ratio is too lean in concentrate.

5. A combined flow rate that is at the desired flow rate and where theratio is too rich in concentrate.

6. A combined flow rate that is at the desired flow rate and where theratio is too lean in concentrate.

7. A combined flow rate that is at the desired flow rate and where theratio is neither too rich nor too lean.

The particular condition above is determined at block 324. Those ofskill will also understand that the desired total flow rate and desiredratio are, in practice, predetermined ranges. Thus, if the total flowrate or ratio are within their respective ranges they are considered tobe “correct” and on target. The “narrowness” of each range is settableas is desired for the particular fluids being mixed, and particularlywith respect to the desired degree of accuracy required for theirmixture. Of the two basic variables, total flow rate and ratio, it willbe appreciated that the ratio between the two liquids is generally themore critical issue with the total flow rate being secondary inimportance. In the example of a post-mix dispensing of a beverage, it isof greater importance that the syrup concentrate be mixed at the properratio with the carbonated water diluent than it is that the cup intowhich the total beverage is being dispensed is filled at some desiredrate.

If condition 1 above exists, where the total flow rate is too low andthe mixture having an over preponderance of one of the liquids, in thiscase identified as the concentrate, the control takes the most directaction whereby both the flow rate is increased and the mixture leaned,namely the diluent liquid flow rate is increased, block 328. In otherwords the control takes one action, where possible, to most directly andefficiently correct both out of range problems. If condition 2 exists,it will be clear that the most direct path is to increase theconcentrate flow rate, block 330. Where condition 3 exists the mostdirect path is to decrease the concentrate flow, block 332. If condition4 exists then the diluent flow rate is decreased, block 334. Wherecondition 5 exists, the adjustment is more complicated and requires thatthe concentrate flow first be decreased to get the ratio within rangeand then increasing proportionately the flow of the concentrate and thediluent in a coordinated fashion to move the total flow rate withinrange, block 336. Condition 6 requires that the concentrate flow ratethen be increased to first achieve the correct ratio followed by thecoordinated reduction of both the concentrate and the diluent to get thetotal flow rate within range, block 338. If condition 7 exists, noaction need be taken, block 340. Those of skill can understand that ifone of conditions 1–4 exist, the actions taken at blocks 328–334, maynot result in achieving the desired total flow rate. In other words, theincrease or decrease of the concentrate or diluent that is required toachieve the desired ratio may not be sufficient to achieve the desiredtotal flow rate. Thus, if the total flow rate of the water and syrup istoo low they both are coordinately increased to achieve the desiredtotal flow rate, and conversely if the flow rates of both theconcentrate and diluent are too high they are coordinately decreased toachieve the desired total flow rate. At block 342 it is determined ifthe pour is ended and if so the routine is stopped at block 344,otherwise the sensing and pour routine continues.

1. A dispensing valve for mixing and dispensing first and second fluidsat a predefined ratio, comprising: a dispensing valve body having firstand second channels for connection to respective sources of the firstfluid and second fluids; first and second fluid flow sensing means forsensing respective flows of the first and second fluids through saidfirst and second channels; a controller coupled to said first and secondfluid flow sensing means for receiving indications of the flows of thefirst and second fluids through said first and second channels; a firstvalve coupled to said first channel, said controller being coupled tosaid valve for operating said valve to control a flow of the first fluidthrough said first channel; and a second valve coupled to said secondchannel, said second valve including a valve member movable between afirst position fully closing and a second position opening said secondchannel for controlling flow of the second fluid through said secondchannel, and an actuator coupled to said valve member and to saidcontroller for being operated by said controller to move said valvemember between said first and second positions and to all positionstherebetween to control the flow of the second fluid through said secondchannel, said controller regulating the flow of the second fluid throughsaid second channel as a function of the sensed flow of the first fluidto maintain the predefined ratio therebetween.
 2. A dispensing valve asin claim 1, wherein the first fluid is a syrup concentrate and thesecond fluid is a diluent.
 3. A dispensing valve as in claim 1, saidfirst fluid flow sensing means comprising a pressure based flow sensingmeans including an orifice plate in and extending across said firstchannel and having a hole therethrough, and means for sensing thepressure of fluid in said first channel on at least one side of saidplate.
 4. A dispensing valve as in claim 3, wherein said orifice plateis chamfered on at least one side thereof around said hole.
 5. Apparatusfor providing a mixture of at least two fluids, comprising: a firstfluid supply line connectable to a source of the first fluid; a secondfluid supply line connectable to a source of the second fluid; a mixinghead fluid coupled to said first and second fluid supply lines forreceiving and mixing the first and second fluids; means for controllingflow of the second fluid through said second fluid supply line to saidmixing head; an orifice plate having an orifice arranged to vent toatmosphere, said first fluid supply line passing through said orifice; acontroller; and a pressure transducer coupled to the first fluid in saidfirst fluid supply line upstream from said orifice plate for measuringthe pressure in the first fluid thereat and for providing indications ofthe measured pressure to said controller, said controller beingprogrammed with flow values determined for a range of pressures of thefirst fluid and to control the flow of the second fluid to said mixinghead in response to the flow of the first fluid in a manner to provide adesired flow ratio of the two fluids.
 6. Apparatus as in claim 5,including a flow turbine in said second fluid supply line for sensingflow of the second fluid.
 7. An apparatus as in claim 5, including anon/off valve in said first fluid supply line upstream from said orificeplate and pressure transducer.
 8. An apparatus as in claim 7, whereinsaid on/off valve, when on, provides a particular nominal flow of thefirst fluid and said pressure transducer measures any fluctuations aboveand below said nominal flow.
 9. An apparatus as in claim 8, wherein saidon/off valve has a manual adjuster to set said nominal flow of the firstfluid.
 10. An apparatus as in claim 5, wherein said means forcontrolling flow of the second fluid through said second fluid supplyline to said mixing head includes a valve coupled to said controller forbeing operated by said controller between a valve closed position and avalve open position and to all positions therebetween to provide desiredfluid flows of the second fluid through said second fluid supply line.11. An apparatus as in claim 5, wherein said orifice plate isimmediately upstream of an outlet from said first fluid supply line tosaid mixing head.
 12. An apparatus as in claim 5, wherein saidcontroller provides a profiled dispense of the first and second fluidsto said mixing head.
 13. An apparatus as in claim 5, wherein saidcontroller provides for dispensing to said mixing head an initialportion of the first and second fluids at a relatively low flow rate, asucceeding portion of the fluids at a higher flow rate and a finalportion of the fluids at a lower flow rate.
 14. An apparatus as in claim5, including a temperature sensor in at least said first fluid supplyline and coupled to said controller, said controller determining flowvalves for a range of pressures of the first fluid as adjusted byviscosity changes of the first fluid as indicated by the sensedtemperature of the first fluid.
 15. A method of dispensing a mixture ofat least two fluids, comprising the steps of: coupling a first fluidsource to a mixing head through a first fluid supply line; coupling asecond fluid source to the mixing head through a second fluid supplyline; flowing fluid in the first fluid supply line to the mixing headthrough an orifice in an orifice plate; sensing the pressure of thefluid in the first fluid supply line on the upstream side of the orificeplate; determining the flow of the first fluid through the first fluidsupply line as a function of the sensed pressure of the first fluid; andcontrolling the flow of the second fluid through the second fluid lineto the mixing head in response to and in accordance with the determinedflow of the first fluid to provide a desired flow ratio of the first andsecond fluids to the mixing head.
 16. A method as in claim 15, includingthe step of venting to atmosphere the first fluid supply line on thedownstream side of the orifice plate.
 17. A method as in claim 15,including the step of sensing the temperature of at least the firstfluid, wherein the sensed temperature is representative of the viscosityof the first fluid, and controlling said determining step as a functionof the sensed temperature of the first fluid, so that the flow of thefirst fluid through the first fluid supply line is represented by boththe sensed pressure and temperature of the first fluid.
 18. A method asin claim 15, wherein the first fluid source is a source of concentratedsyrup and the second fluid source is a source of water.
 19. A method asin claim 15, including the step of controlling the flow of the firstfluid over a range of flows.
 20. A method as in claim 15, including thestep of measuring the flow of the second fluid through the second fluidsupply line.
 21. A method of dispensing a mixture of at least twofluids, comprising the steps of: coupling a first fluid source to amixing head through a first fluid supply line; coupling a second fluidsource to the mixing head through a second fluid supply line; flowingfluid in the first fluid supply line to the mixing head through anorifice in an orifice plate; measuring a pressure drop in the firstfluid passing through the orifice; determining the flow of the firstfluid through the first fluid supply line in accordance with and over arange of measured pressure drops; and controlling flow of the secondfluid through the second fluid supply line to the mixing head inaccordance with said determining step to obtain a desired flow ratio ofthe two fluids to the mixing head.
 22. A method as in claim 21,including the step of venting the first fluid supply line to atmospheredownstream of the orifice plate, wherein said measuring step measuresthe pressure of the first fluid substantially immediately upstream anddownstream from the orifice plate.
 23. A method as in claim 21,including the step of sensing the temperature of at least the firstfluid, wherein said determining step comprises determining the flow rateof the first fluid through the first fluid supply line both inaccordance with and over a range of measured pressure drops and inaccordance with the viscosity of the first fluid as represented by thesensed temperature of the first fluid.
 24. A method as in claim 21,wherein the first fluid is one of a plurality of concentrated syrups andthe second fluid is water.
 25. A method as in claim 21, including thestep of controlling the flow of the first fluid to be within a range offlows.
 26. A method as in claim 21, including the step of monitoring theflow of the second fluid.
 27. A dispensing valve for dispensing firstand second liquids therefrom at a desired ratio, comprising: a nozzlebody assembly having first and second liquid flow passages havingrespective first and second inlets and first and second outlets forrespective flow therethrough of the first and second liquids; a firstliquid flow body assembly of the nozzle body assembly, said first liquidflow body assembly having a first liquid flow cavity fluid coupled at anoutlet end thereof with said inlet to said nozzle body first liquid flowpassage, said first liquid flow body assembly further including a valvemember and an actuator for moving said valve member continuously betweena first position where a liquid flow path through said first liquid flowcavity is fully closed and flow of the first liquid through said firstliquid flow cavity is stopped, a second position where said liquid flowpath is open for flow of the first liquid through said first liquid flowcavity and all positions between said first and second positions forregulating flow of the first liquid through said first liquid flowcavity as a function of the position of said valve member between saidfirst and second positions; a first flow sensor for sensing flow of thefirst liquid through said first liquid flow cavity of said first liquidflow body assembly; a second liquid flow body assembly having a secondliquid flow cavity fluid coupled at an outlet end thereof with saidinlet to said nozzle body second liquid flow passage, said second liquidflow body assembly further including valve means in said second liquidflow cavity for interrupting or establishing liquid flow therethrough; asecond flow sensor for sensing flow of the second liquid through saidsecond liquid flow cavity of said second liquid flow body assembly; andcontrol means for receiving inputs from said first and second flowsensors and connected to said first liquid flow body assembly actuatorfor operating said actuator to move said valve member relative to saidfirst and second positions to regulate flow of the first liquid throughsaid first liquid flow cavity in accordance with the sensed flow of thesecond liquid through said second liquid flow cavity.
 28. A dispensingvalve as in claim 27, wherein said first liquid flow body assemblyactuator comprises proportional motor means for moving said valve memberand said second liquid flow body assembly valve means comprises valvemeans.
 29. A method of controlling a valve for dispensing two liquids ata determined ratio, said method comprising the steps of: providing avalve body having fluidly separate first and second liquid flow passageshaving respective first and second inlets and first and second outlets;coupling the first and second liquid flow passage inlets to respectivesupplies of first and second liquids; connecting an actuator to thevalve body for moving a valve member in the first liquid flow passagebetween a first position where the first liquid flow passage is fullyclosed and flow of the first liquid through the first liquid flowpassage is stopped, a second position where the first liquid flowpassage is open and flow of the first liquid through the first liquidflow passage is established and to all positions between the first andsecond positions to regulate flow of the first liquid through the firstliquid flow passage; controlling flow of the second liquid through thesecond liquid flow passage; sensing flow of the first liquid through thefirst liquid flow passage; sensing flow of the second liquid through thesecond liquid flow passage; monitoring the sensed flows of the first andsecond liquids through the first and second liquid flow passages; and inresponse to said monitoring step and while the first and second liquidsare flowing through the first and second liquid flow passages,controlling the valve body actuator to move the valve member topositions relative to said first and second positions to adjust flow ofthe first liquid in relation to flow of the second liquid to dispensethe two liquids at the determined ratio.
 30. A method as in claim 29,comprising the further steps, performed prior to said monitoring step,of: initiating flow of the first liquid through the first liquid flowpassage by controlling the valve body actuator to move the valve memberto a predetermined position and controlling flow of the second liquidthrough the second liquid flow passage to establish flow of the secondliquid, and then sensing the flows of the first and second liquids fromthe point each begins to flow; determining a total dispense ratio of thefirst and second liquids as a function of the total volume of eachliquid dispensed; and controlling the valve body actuator to move thevalve member to either decrease the flow of the first liquid if a firstdetermined dispense ratio is greater than a predetermined total dispensepositive ratio error limit and if a ratio determined subsequent to thefirst determined total dispense ratio is greater than a predeterminedpositive ratio error limit where the total dispense positive ratio errorlimit is less than the positive ratio error limit, or to increase theflow of the first liquid if the first total dispense ratio is less thana predetermined total dispensed ratio negative error limit and if asecond ratio determined subsequent to the first determined totaldispense ratio is less than a predetermined ratio negative error limit.31. The method as defined in claim 29, comprising the further steps,performed prior to said monitoring step, of: initiating flow of thefirst liquid through the first liquid flow passage by controlling theactuator to move the valve member away from said first position to apredetermined position, and then after lapse of a predetermined timefollowing performance of said initiating step, controlling flow of thesecond liquid through the second liquid flow passage to establish a flowof the second liquid.
 32. A dispensing valve for dispensing two liquids,comprising: a water body assembly having a water flow channel forconnection to a source of water and means for regulating a flow of waterthrough said water flow channel; a syrup body assembly having a syrupflow channel for connection to a source of syrup and means forregulating a flow of syrup through said syrup flow channel; a nozzlebody having a water flow channel and a syrup flow channel, said nozzlebody releasably securing said water body assembly and said syrup bodyassembly thereto such that said nozzle body and water body assemblywater flow channels are fluid coupled and such that said nozzle body andsyrup body assembly syrup flow channels are fluid coupled; and adischarge nozzle, said nozzle body water and syrup flow channels beingfluid connected to said discharge nozzle.
 33. A dispensing valve fordispensing a desired ratio of two fluids, comprising: a first fluid bodyassembly having a first fluid flow channel for connection to a source ofa first fluid, said first fluid body assembly having means forregulating a flow of the first fluid through said first fluid flowchannel, said regulating means including a first valve member, a flowcontrol element in said first fluid flow channel and drive means formoving said valve member from a first position closing said flow controlmember to a second position opening said flow control member and to allpositions between said first and second positions, said drive meansmoving said valve member to a plurality of positions between said firstand second positions corresponding to a plurality of first fluid flowsthrough said first fluid flow channel so that the flow of the firstfluid through said first fluid flow channel is regulated as a functionof the position of said valve member relative to said flow controlelement; a second fluid body assembly having a second fluid flow channelfor connection to a source of a second fluid, said second fluid bodyhaving means for regulating a flow of the second fluid through saidsecond fluid flow channel; a nozzle body having first and second fluidflow channels, said nozzle body releasably securing said first andsecond fluid body assemblies such that said nozzle body and first fluidbody assembly first fluid flow channels are fluid coupled and such thatsaid nozzle body and said second fluid body assembly second fluid flowchannels are fluid coupled; a discharge nozzle, said nozzle body firstand second fluid flow channels being fluid connected to said dischargenozzle; first and second fluid flow sensing means in said first andsecond fluid flow channels for sensing flow of the first and secondfluids; and control means coupled to said first and second fluid flowsensing means for receiving sensed flow rates of the first and secondfluids, said control means controlling operation of at least one of saidregulating means of said first and said second fluid body assemblies asa function of the sensed flow rates of the first and second fluids sothat the first and second fluids are dispensed out said discharge nozzlein a predetermined ratio.
 34. A dispensing valve as in claim 33, saidcontrol means controlling operation of said first fluid body assemblyregulating means during dispensing of the first and second fluids out ofsaid discharge nozzle.
 35. A dispensing valve as defined in claim 33,said drive means comprising linear actuator means.
 36. A dispensingvalve as defined in claim 33, wherein said first and second fluid bodyassemblies are releasably securable to said discharge nozzle.